This invention relates to automotive switches, and more particularly to a combination brake and clutch-pedal operated switch which automatically adjusts to compensate for any change in the stop positions of the associated pedals.
Contemporary motor vehicles utilize a variety of pedal-operated electrical switches for controlling safety signals or warning devices The brake pedal, for example, has long been utilized to operate a switch which controls the tail lights of a vehicle; and more recently additional switches such as cruise control and start enable switches have been incorporated in automotive vehicles to respond to the manipulation of an associated clutch pedal, brake pedal or transmission shift lever.
One of the problems inherent in switch mechanisms of the type described is that after prolonged use the associated pedals or levers may not always start from or stop in the same position--i.e. the "throw" of the pedal changes with prolonged use. Consequently, unless the mechanism has incorporated therein some means to compensate for variations in the throw or movement of the associated actuating element, the switches will not be properly operated.
U.S. Pat. No. 4,604,506 discloses a self-adjusting switch mechanism of the type in which a brake pedal operates a pivotal actuating arm, which is frictionally coupled to a pivotal switch actuator. The actuator carries a plurality of arcuate, radially spaced switch contacts that pivot in a first plane in response to corresponding movement of the actuator. The contacts have sliding engagement with a plurality of stationary contacts that are fixed in a second plane parallel to the first plane, and which represent several different switches, such as for example a cruise control switch, a transmission control switch, and a brake lamp switch. The switch actuator is mounted for limited pivotal movement, so that in the event that the brake pedal causes the actuating arm to pivot for angular distances greater than its original calibration, the frictional coupling will simply let the actuator arm pivot relative to the actuator to absorb the excess throw of the actuator arm. Operation of the switches therefore remains the same, notwithstanding changes in the throw of the actuating arm.
A primary disadvantage of this known mechanism, however, is that it is designed solely for operation by the brake pedal, and therefore is suitable for use only with vehicles which have automatic transmissions. Moreover, such mechanism is rather expensive and difficult to manufacture.
It is an object of this invention, therefore, to provide an improved switch mechanism of the type described which is designed for use selectively with either automatic or manual transmissions, and which, in either case, automatically compensates for any change in pedal throw which may occur during use of the mechanism.
Still another object of this invention is to provide an improved switching mechanism of the type described which is relatively inexpensive to manufacture and assemble as compared to prior such mechanism.
Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawings.